One type of well known juice extractor includes a series of juice extractor units that are ganged together. Each juice extractor unit includes upper and lower cups for supporting the fruit. The sides of both upper and lower cups have fingers that intermesh or interdigitate together. The upper cups are mounted on a common cross bar, which moves in a fixed up and down path by means of a cam-drive positioned at the top of the juice extractor machine. The upper cups move into the bottom cups, which remain rigidly positioned.
A fruit, such as an orange, is initially fed into the bottom cup by a cam-operated feeding device, which deposits the fruit in the bottom cup. The upper cup then descends into the lower cup. The fruit is pressed against sharp circular cutters positioned at the top of a strainer tube adjacent the lower cup, and an upper cutter positioned in the upper cup. The two circular cutters cut plugs into both the top and bottom portions of the fruit as the interdigitating fingers of the two cups mesh together. At the same time, the inner portions of the fruit (i.e., the pulp and juice) are forced down into the strainer tube positioned within a manifold. The peeled surfaces of the fruit do not contact the juice as the interdigitating fingers peel the fruit. After the upper cup has descended toward the lower cup, an orifice tube moves upward into the strainer tube. The orifice tube includes a restrictor in its lower end. The orifice tube applies pressure into the internal portion of the strainer tube to separate juice and pulp within the strainer tube, collect the core material and discharge the core material out of the bottom of the orifice tube. The core material typically includes membrane, seeds and peel plugs.
Typically, the upper and lower cups, orifice tube and strainer tube each form a single juice extractor unit. A number of these units are ganged together within a common frame and forms the juice extractor machine. A drive mechanism engages a mounting assembly that is positioned on the orifice tube and reciprocates the orifice tubes together within the respective strainer tubes. Typically, the drive mechanism is formed from a beam that is vertically moveable on bushings by a cam-driven mechanism.
In order to compensate for any mechanical misalignment, a bearing collar and hemispherical alignment bearing has been positioned in an oil bath with hold-down springs to tie the bearing assembly together. The assembly is interposed between the orifice tube and the mounting assembly to allow the orifice tube to swivel relative to the mounting assembly and reciprocating drive mechanism, such as the drive beam. Typically, the mounting assembly and other components were formed of metal creating an undesirable metal-to-metal contact within the oil bath. The hold-down springs allowed some movement of the mounting assembly and other components over the hemispherical ball of the bearing. Because of the metal-to-metal contact, the lubricated oil bath became important to maintain machinery operability. However, the foreign material sometimes mixed with the oil bath and, thus, the lubricating surface was lost, which could cause operational difficulties. Additionally, the oil had to be replaced every year.